TryGGER:Application of tryptophan Florescence Sensors for improved raw water quality monitoring of Faecal Contamination in Groundwater sources

Groundwater is a hugely important natural resource, providing the majority of drinking water globally, some 35% of drinking water in the UK, and up to 80% in southern England. High frequency real-time systems are now widely used in water industry for water quality monitoring, however transient microbiological contamination is currently still monitored using traditional spot sampling and culturing techniques. The highly dynamic nature of microbiological contamination necessitates high frequency on-line monitoring for the optimisation of down-stream processes such as treatment and distribution. We propose to pilot and embed within the UK water industry the use of new fluorescence sensors to enable this. In addition, while it is generally understood that high levels of faecal contamination in groundwater may be accompanied by relatively high turbidity, this is often not the case, and depends on the source and pathway of faecal contamination in the subsurface.

Differentiation of turbidity derived from aquifer material or induced by pumping and that derived from microbial contaminants has significant potential benefits to the water industry through treatment process optimisation. Water companies in England and Wales have invested £42 million on investigations into source water characterisation and treatment process optimisation from 2010 - 2015 (OFWAT 2009) but understanding transient microbial contamination remains a significant challenge.

Recent NERC funded research on in-situ fluorescence spectroscopy, now a well-established technology, offers a highly sensitive method to achieve this for raw groundwater sources. Through a partner led process we have developed a proposal to pilot, embed and develop an implementation strategy for this technology that is relevant for the UK water industry, but is also highly relevant for international water and health sector organisations. As part of this proposal, placement activities within two UK water companies (Affinity Water and Wessex Water) will be carried out to i) pilot and embed the use of tryptophan sensor technology in the UK water industry for improved monitoring of microbiological contamination in vulnerable groundwater sources, ii) provide robust evidence on the suitability of the current turbidity trigger (1NTU) for groundwater quality assessments, iii) provide an implementation strategy for this technology within the UK water sector through user-led collaboration. This will be carried out though visits to all UK water companies to obtain feedback on how this could benefit and be implemented in different parts of the water sector and disseminate findings with potential new end users.

Working with key partners from across the UK water industry, including water companies (Affinity Water and Wessex Water) and cross-sector organisations (UKWIR, Water UK and DWI), TryGGER aims to embed within the UK water sector the use of on-line sensors for monitoring dynamic microbiological contamination in groundwater sources for improved use of water resources and optimisation of treatment processes. The application of this sensor technology will be piloted in four case study sites in the UK, through placement activities undertaken by BGS scientist in water industry partners. These have been selected in consultation with water utilities to be representative of vulnerable groundwater settings, with wide applicability both within the UK context and globally. Importantly, a strategy for implementing the use of these sensors for raw water quality monitoring will be developed with end users from across the UK water industry as part of this proposal to enhance wider uptake of this technology.

This proposal has the potential for far reaching impact in the UK water industry and further afield. Involvement of the main players in the water industry, as well as utility firms, from early on during proposal development this has ensured that is highly relevant to the end-user community.

TryGGER will deliver impact that will benefit a wide range of stakeholders within the water sector in the UK, and has potential to have significant impact beyond the UK water sector. It will catalyse and accelerate the uptake and impact of NERC generated research on fluorescence sensor technology and implant this firmly within the water industry. It has real potential to provide a step change in the way raw microbiological water quality is monitored within the water industry and a tangible impact on down-stream water treatment processes as well as reduction costs associated with turbidity driven waste of water resources and energy. Key factors in the take up of any new technology are real demand, the mechanism of delivery and the long-term sustainability of the technology. Through end-user involvement from the outset of putting this proposal together, we have already established that there is significant interest within the water sector for an on-line system for monitoring changes in microbiological water quality.

It is the partner utility companies that have identified where this technology could enhance the operation and management of raw water sources, as well as the links to more effective treatment, greener technology and reductions in running costs. This technology will be demonstrated and embedded within two water companies at four public drinking water supply sites which have significant issues related to transient turbidity and microbiological contamination. Strong partners from industry, including manufactures of the sensors; end-users in the water industry and regulatory sector; and the expertise from BGS in the deployment, interpretation and assessment of this technology ensures that there is the team and mechanism in place to deliver significant impact. Involvement of representatives of cross-sector organisations, such as UKWIR and Water UK, will ensure that the impact from TryGGER will be rapidly disseminated and taken up throughout the water industry.

The capital costs and running cost for this type of technology is considered low, given the potential benefits and the overall running and treatment cost associated with public drinking water supply. Furthermore, it is anticipated that as this tool is taken up within the industry the demand generated will reduce the capital cost due to increased competition and economies of scale in production. This will make it beneficial to use this technology more widely within the water industry, perhaps within pipe networks or treatment sites in the UK, as well as more affordable for applications globally, particularly within the international development context. It is important to note that BGS has been particularly effective with regards to delivering impact from the national good work they undertake as reflected by the recent NERC review of Centre/Surveys. TryGGER will:

i) Implant within the UK water industry the knowledge of this new technology for monitoring raw groundwater resources. Direct beneficiaries will be the two water companies who will provide case studies for this technology; however, there are many other water companies across the UK who will be involved directly in this proposal through placement and dissemination activities.
ii) Embed wider use of in-situ technology within the industry for understanding of transient faecal contamination is groundwater. This has wide implications for managing supplies and carrying out water treatment with broad impact in UK water industry.
iii) Improve the evidence base and justification of 1NTU criteria currently used by the UK water industry. This has broad impact for water quality strategy and monitoring (e.g. DWI) for the UK and elsewhere.
iv) Build on evidence base from NERC research for the use of telemetered smart sensors in UK industry for real-time faecal monitoring. TryGGER will demonstration of application of this technology for public drinking water supply from groundwater.